WASHINGTON (AFP) - US naval investigators are probing allegations that Marines distributed nude pictures of female service personnel taken without their knowledge, officials said on Monday (Mar 6, 2017).

The explicit photos, shared on a secret Facebook page which has since been taken down, reportedly showed female Marines and other women in various states of undress.

Posts on the website, called "Marines United", also contained lewd comments about some of the women.

"The Marine Corps is deeply concerned about allegations regarding the derogatory online comments and sharing of salacious photographs in Marines United, a closed website," the United States Marine Corps (USMC) said in a statement on its website.

"This behaviour destroys morale, erodes trust and degrades the individual. The Marine Corps does not condone this sort of behaviour, which undermines its core values."

Because the Marine Corps is part of the Department of the Navy, the scandal is being investigated by the Naval Criminal Investigative Service (NCIS).

"NCIS is investigating those who are posting explicit photos without the permission of the person in the photos, which is potentially a felony. Beyond that, NCIS does not discuss the details of ongoing investigations," the agency said in a statement.

Fox News reported that those with access to the site included active-duty and retired male Marines, Navy personnel and British Royal Marines.

The head of the US congressional committee that oversees the military called the website "unacceptable." "Revelations of this sort of treatment against fellow Marines are troubling," said Mac Thornberry, chairman of the House Armed Services Committee.

"Degrading behaviour of this kind is entirely unacceptable. They and the nation deserve better.

"I expect the Marine Corps to investigate this matter fully with appropriate consequences for those who willingly participated."